Vehicle wheel suspension



April 21, 1953 Filed July 26, 1949 K. w. TANTLINGER 2,635,896

VEHICLE WHEEL SUSPENSION '7 Sheets-Sheet l April 21, 1953 K. w. TANTLINGER VEHICLE WHEEL SUSPENSION 7 Sheets-Sheet 2 Filed July 26, 1949 INVENTOR.

April 21, 1953 K. w. TANTLINGER 2,635,896

VEHICLE WHEEL SUSPENSION Filed July 2e, 1949 7 sheets-sheet s April 21, 1953 K. w. TANTLINGER 2,635,896

VEHICLE WHEEL SUSPENSION Filed July 26, 1949 7 Sheets-Shrewl 5 IN V EN TOR.

@E f Wer -Bz ww E April 21', '1.'953 K. w. TANTLINGl-:R 2,635,896

VEHICLE WHEEL SUSPENSION Filed July 26, 1949 7 Sheets-Sheet 6 fes' /ZZ /za Hf .9 I f j? 56 INVEN TOR.

Z 0 6 7 f w w m www. m m, m e n d. m @mi U 7 M M v y N ,0o B R m f E M j .6 G E Q u w /X T mm w f f2 E wm m n 4 m m H /4 n T I 9 ,3 m... f .QDv 6, /0, 1N 2 1. ly in n .ww VM .n w D. l l A u Patented Apr. 21, 1953 "ITSED PATIFINT l OFFICE 22,635,896 n VEHICLE AWHEEL SUSPENSION Keith Tantlingen Spokane, wash., assigner ito Brown 'Trailerslnc., SpokanefWashya cor- '.porationof-Washington a lApplicationJuli-y26, 1949, .Serial `N0..l06.8`7.1l

,The present .invention relatesto improvements in-a :vehicle .wheel` suspension.

The :principal purpose of my invention is :to provide -a .means .to .spring support the vehicle from the wheels whichis adapted 'to providethe minimum .unsprung .weight .in combination with spring .support mechanism 'for the Lload `that varies in .stiffness `with load increase .and docreaseso as .to lfproyicleso'ft riding over 'therange of .loadingffrom empty l-to .capacity weight.

r.lin .all 1load bearing vehicles where the "load is spring supported, `the desired result isto provide a ,yieldability ,of the `spring .means that will `.give the ,optimum .ease of .ride or freedom from vibrations that ,are communicatedfthrough .the wheels.` In .present known devices, .the supports provid,- ing this ease at ffullload .are .too stili at .light load or no load. Inparticular this is important in large .trucks and trailers making .longhauls Onelload may be quiteiheavy Vandtax the weight carrying capacity .off the vehicle. The spring support for this condition ,must `provide lrigidity enough to lkeep the body from .dropping so 'low as to cause contact with .or .diii'iculty with .the running gear. On .the return Ltrip the `same vehiclemay carry a cargo which has .more bulk but whichhas only .a .fraction ofthe weightof the lirst load. fThe more' bulky .and lighter :products usually are morefragile `and need the. greatestprotectionjfrom road shocks and vibration.

More .specifically it is, `therefore, .a .purpose .of my invention to `provide a wheel .mounting for vehicles including aresilient element that is tensoned increasingly ,at an .accelerating rateaslthe load 'is increased, with `.et-minimum variation .of elevation'between wheelwand load. To `this en'd my invention contemplates .an embodiment wherein a trailing .arm, pivoted Lon the yehicle body, has the wheel `,at or near its ree,end,.,an'd a '.load `strut is 'linked to .the trailing .arm .to .extend upwardly and away `from 'the arm `to .the body. These are lcombined with `one or more torsional springs connecting the 'load .strut 4.to the "body in suchffashionrthalt increasing'load Yon the wheel .decreases the eiectve .action Eof .the load strut on the spring atan increasing rate.

:Itis a `further object of this invention .to provide in the .aforesaid embodiment .a wheel mounting :that .mounts the wheels ,individually ,on .op-` posite sides of thetrailing arm, with individual braking applicable to each wheel.

Another object `of the invention .is the `provision of a vnovel connection, including the` trailN ing arm and load strut, for establishing and maintaining Aproper `cai'nber `and "caster 'for the individual wheel units. The word camber, as used herein, refers to theinclination of the wheel with .respect .to .the vertical. The word caster as used herein .refers .to .the toe in or "'toe out eof .the `wheel lwith .respect to Vthe line .of trauelo the vehicle.

:Another object of .the invention is ,the .provision .of a ,tandem arrangement .of wheels `with trailing arms .and load struts .and l a `compression strut `with torsional ...springs .operable when rthe forward or `rear -rnember of the Atandenri drops suddenly finto .a depression tto .shift the other member and the spring loading to .adapt the wheelsto fthe .changed l'terrain .whilemaintaining optimum spring support of the loadand Iminimumshittinelevationiof .thefload Still another object of the invention is -the provision of a torsional `Sprit.1s-,to load .strut-t0 body, connection., operable automatically `.to maintain the dead strut thrust -Hcentered von a line through the body-to-slpringeconnection., :with the torsional :spring moy-ing :about the hod-yftospring connection, to accommodate for increasing :and decreasing the :loadingT A of '.the aspiring 'Pby the.endithrustoftheloadstrut.

`My improved wheel suspension is particularly advantageous in reducing `:the wear Land thea-tion the itires. 4.According :to the .construction ffwhen dual `.wheels sare mused the V:individual tires Aof a pair are :spaced apart substantially `and since each tire rolls independentlythere -is no scuing between 1^the --dual tires no `matterswhat the rcondition *of lthe `roads l or vtires Vmay be. The 'freedom from scuiiing permits the tires torunmuch cooler and wide kspacing `also "helps to cool `the tires. IThe `advantages Aof this construction are particularly noticeable `in elimination of `the dragging of one AwheelV by `another in making .a turn. sharp turn will cause the outer Wheel of a pair Ato make a `complete revolution more tha-nthe inner wheel. This means 4.thatfor each turnione'tire mustbe skidded a distance .equal .to its Vcircumference if the wheels are secured .together. With -my construction neither wheel causes Athe other tofskid.

A further object .of the present .invention `is to g-provide a wheel suspension mechanism lfor A vehicles :embodying .means .to mount two 4.wheels side by .side wherein the wheel bearings.andttires are accessible with .respect .to either .wheel for checking or ...removal .by .merely elevating `the other wheel. The .arrangement 1is suchithatfthe wheels o1' .a Lpair are 'separated .hy .-the )support arm `and the compression strut to effecta rela;

tively wide distribution of tire surface in contact with the roadway transversely of the vehicle. An additional feature and advantage in this respect is the utilization of the trailing support arm to provide brake connections to the individual wheels.

Another object of the invention is to provide a wheel suspension of the character described embodying the trailing arm and a compression strut with a torsional spring mounting for the compression strut together with means for varying the load height to accommodate varying loading levels encountered. Y

The foregoing objects and advantages together with additional objects of my invention will be described more fully hereinafter in the detailed description of a preferred embodiment of my invention shown in the accompanying drawings. It should be understood however, that the drawings and description are illustrative only and are not to be considered as limiting my invention except insofar as it is limited by the claims.

In the drawings:

Figure 1 is a View in side elevation of a wheel suspension embodying my invention;

Figure 2 is a plan view taken substantially on the line 2-2 of Figure 1 with the vehicle body left olf, illustrating the wheel suspension mechanism as it appears when viewed from the top and utilizing dual wheels in tandem;

Figure 3 is an enlarged fragmentary sectional View taken on the line 3-3 of Figure 2;

Figure 4 is a sectional view taken on the line 4 4 of Figure 1;

Figure 5 is a sectional view taken on the line 5-5 of Figure 1;

Figure 6 is a sectional view taken on the line `i--I of Figure 1;

Figure "I is an enlarged fragmentary sectional View taken on the line 1--1 of Figure 2;

Figure 8 is an enlarged sectional view taken on the line 8-8 of Figure '1;

Figure 9 is a sectional view taken on the line 9--9 of Figure 2;

Figure 10 is a plan view similar to Figure 2 of the wheel suspension illustrating its construction when only a single pair of dual wheels is used at each side of the Vehicle;

Figure 11 is a sectional view taken substantially as indicated on the line I I-I I of Figure 10;

Figure 12 is a sectional view taken on the line I2-I2 of Figure 11;

Figure 13 is an enlarged fragmentary sectional view taken on the line I3--I3 of Figure 12 illustrating a changed position;

Figure 14 is a plan view partly in section of the wheel axle and brake assembly utilized in mounting the wheels on the wheel arm; and

Figure 15 is a fragmentary side View of the wheel mounting and wheel arm assembly taken substantially on the line I5-I 5 of Figure 1.

Referring now in detail to the drawings and particularly to Figures 1 to 9 inclusive, these figures will illustrate my invention as applied to a vehicle Wheel suspension that utilizes four wheels as a unit, the wheels being arranged in front and rear pairs. The four wheels II, I2, I3 and I4 are individually mounted so that each wheel can rotate independently of the others. Mounting brackets I5 and I6 at the forward end of the wheel assembly are secured to the vehicle body and mount a trailing wheel arm I1 which has a wheel axle I8 at its lower end for mounting the wheels II and I2. A load strut I9 is pivotally connected at its lower end to the wheel arm I1 '4 so that the strut I9 is likewise supported by the axle I8 and the wheels II and I2.

A second pair of brackets 20 and 2| also mounted to the body I8 serves to mount a torsional spring assembly 22 and a second trailing wheel arm 23. The trailing wheel arm 23 has an axle 24 at its lower end on which the wheels I3 and I4 are mounted. A second load strut 25 is pivotally secured to the lower end of the trailing wheel arm 23.

A third pair of brackets 26 and 21 also mounted on the body I0 serves to mount a torsional spring assembly 28 for the load strut 25. The torsional spring assemblies 22 and 28 have their central tubes 29 and 38 linked together by lever arms 3| and 32 and a compression link 33 which can be adjusted in length.

The torsional spring assemblies 22 and 28 are of the same general construction. These spring assemblies provide the means by which the yielding support of the body I0 is accomplished. In order that the function of the remainder of the mechanism in combination with these assemblies will be more clearly understood, the detailed construction of the torsional spring assembly is given at this point.

Each torsional spring assembly is made up of two co-axial tubes (see Figures 6 and 9). The inner tube 29 extends beyond the -outer tube 34. The outer tube 34 is made up of two half sec-i tions which have ilanges that are secured together byv Welding and the flanges are apertured to receive a series of bolts 35. The yieldability Vof the torsional spring is provided by a rubber sleeve 36 that fills the space between the members 29 and 34 and is bonded directly t-o the metal of these members. This type of torsional spring con-v struction is commonly referred to as a torsilasticv spring. It will be appreciated that if the shellr member 34 is rotated with respect tothe tube 29, the rubber 36 will yieldingly oppose such rotation. A torsional spring of this construction is highly advantageous for my purpose since it can be made with adequate strength and size to carry the tremendous loads necessary in a heavy load carrying vehicle such as a large highway trailer that carries several tons. It provides a spring in which there is no rubbing of metal against metal and in which there are no parts to come loose.

The tube 29 is provided at one end with a pivot bushing 31 (see Figure 6) that has a reduced extension 38 extending into the bracket 2 I. The pivot bushing 31 is of course, permanently secured on the tube 29. The bracket 2| has a tapered aperture 39 which receives a tapered rubber bush.

ing 40. The rubber bushing is under compression in the aperture 39. It is held by a cap plate 4I that is secured on the end of a rod 42 which extends through the tube 29. At the other end of the tube 29 a lever arm mounting member 43 is secured. This member has a cylinder portion 44 that extends through an aperture 45 in the bracket 20. A rubber bushing 46, identical with the bushing 40, is under compression in the aperture 45. The member 43 has a squared extension 41 that mounts the lever arm 3I which is provided with a hub portion that has a squared aperture. The lever arm 3|, hereinafter sometimes referred to as a pitman arm is held on the portion 41 of the member 43 by a cap washer 48 and a nut 49.

The torsional spring assembly 28 is identical tion of one will suiice for both. It will be noted that the torsional springs are so mounted in the brackets that theycan rotatesince the bushings` III!` and 48 will yield and permit whatever rotation is necessary. The tubes29 and 30 however, are xed with respect to the pitman` arms 3| and32`. Yokes 59 and 5| at the opposite endsof the link 33 are connected tothe arms- 3| and 32 in the manner shown in Figure 6i A tube 52andrubber bushings 53 and 54. provide the connection and are held in place by captwashers 55and 56, a bolt 51 and a nut 58.

Each of the load struts |9 and 25 isconnected to `its respective torsional-spring assembly 22 or 2-0 in themanner illustrated. bestiby Figures l, 2 and 9. `A semiecylindrical mounting platef60 is bolted by the bolts 35 tol the shell member 34 of the torsilastic spring assembly. This plate 80 has welded thereto a pair of short lever arms 8| and 62. The load strut has pivot bushings 63 and 64 extending into the arms 6| and 82 r and mounted by rubber bushings 65 and 68-whichare held in place by cap washers 61 and 68, a rod 69 and a nut 10. The detailsof this construction are illustrated in section` inFigure 12 where the same construction is applied to a modified wheel suspension but does not employ wheels in tandem. With this constructionit is believed to be evident that upward pressure of the load strut I9 will be communicated through the lever arms 6| and |52` to the shell member 3l and the rubber 36. This pressure will tend to rotate thetube 29 and thus transmit movement to the link 33 through the pitman arm 3| and the yoke 50;

The lower end of the load strut I9 is pivotally supported on the lower end of theitrailing wheel arm` |1 in the manner best illustrated by Figures 2, Sand 5. The wheel arm- I1 at its-lower` endis fixed toa sleeve 1I that hasa` mountingbracket 12 Welded thereon and extending rearwardly Vfrom the sleeve 1 I. The bracket 12 has a bearing por'- tion 13 that receives al mounting tube 1li The load strut |9 has a yoke 15 atits lower end that is mounted on the tube 1liA and rubberbushings 16 and 11. Cap washers 18 and 19, ya bolt 80 and a nut 9| securethe partstogether and hold the bushings 18 and 11` undercompression.

It is believed to be clear from the foregoing description that the weight ofthe body l will tend to swing the trailing arm I1 rearwardly andupwardly about its mounting to the brackets I and I E and this will thrust the load strut |9'upwardly to transmit a turning movement to the outer shell member 34 of the spring assembly 22.

The load strut 25 is connected to the trailing Wheel arm 23 by av sleeve 82', a bracket 83 and a yoke 81|` in the same fashion that the trailing wheel arm I1 is connected to the load strut I9.

i' The trailing wheel arms I1 .and 23 are connected to their respective body brackets inthe same fashion. This connection' is'illustrated in Figure 4r of thedrawings. The trailing arms are hollow and havelateral tubular extensions 85 and 88at the upper ends. The extension 85 has' a threaded bushing 81 nxed therein and the extension 85 has a threaded bushing 88 secured therein. An eccentric pivot member 89 is threadedon the bushing 81 and a like pivot member 90 isthreadedon the bushing 88. These members 89 6 inthe" brackets |5 and lrespectively byl rubber. bushings 95 `and 98, capwashersSl and 98, aboli; 99and-a nut |00. The eccentric. pivotrmembers `89 andprovide y a` means for correcting the` alignment of.; the

Wheels securedto thetrailingwheel arms.. Itwill be appreciated that by proper adjustmentV of these pivot` members,` the extension. 8,8. may be made to trailthe extension slightly to cause the wheels and` |2 to `toe in. This adjustment is accomplishedby settingthemembers 8:9 and on their respective bushings 81 and 88 so that the pin portion 92` will be.` nearer the forward edgelof the wheelarm` I1fthanthepinportion 9|. The. pivot membersmay also ,z be `adjusted to lower one extension.. with` respect to` the` other so `as to give-the proper camberftofthe wheels. This is donelby setting the members 89 and 90 on their respective bushings` 81 and: 88 so` that the pin portion 9| is nearer thetopof the wheel arm I1` than the pin` portion 92. It is desirable to` have the wheels toe inslightly and to have them tilted slightly to the vertical. The adjustment provided` by the pivot members 89 and 90 and their connectionl to the trailing wheel arms takes care of this. The load struts I9 and 25 may be con.- nected totheir respective lever arms 8| and 82 by1 like eccentric pivot members ifl desired.

Thepositioni of the Wheel arms I1.v and 23 and the `load struts |9-and 25, as illustratedin Figure l, is that of light load or empty'position. In this position the leverarms` 6| and 62`that connect the load struts to the torsionalspring assemblies 22 and 28 arefsubstantiallyv at` right angles to the loadstruts. The increase of load causes aclocku wise rotation of thelever arms-8| and621 andthis in turn reduces the effective length of the lever arms lilV and 82 asthe levers tend to rotate the outer shellmember 34 ofthe torsional spring. As the load `increases the lever arms are more rapidly reduced in effective length. This is'an important feature of the construction in providing for easy riding throughout the range of loading. It pro-` vides a maximum spring softness-withi no load and increased stiifening of the spring action as the load increases; safety factor, because the leverageon the torsilastic spring decreases toward zero as the' load increases, and in the event of spring failure or a break in the connectinglink 33 orits connections to the members 29 andiiti,` the `.arms Gland 6:2 become merely links connecting the upper ends of theload'strutsto the members 29and` 30.

The link 33 can be lengthened or shortened in the manner illustrated by Figuresland 8 to take care of various load conditions. :Iff the sleeve 33a of the link 33 is rotated in such av manner as to lengthen the link 33, increased tension will beapplied to the torsilastic` springs. Lock nuts 33h and 33e are providedat the ends ofthe sleeve 33aV These hubs carry the usual brake drums |83 and |04 in which the brake shoes |05 and |06 operate, thus each wheel is free to` rotate on the axle |8 and is controlled by itsown individual brake shoe. The brake operating mechanism includes spiders |01 and |08 that carry thebrake-shoes.

These spiders are mounted on the sleeve 1| that is secured to the end of the trailing wheel arm. Cain shafts |09 and |I0 are mounted on the spiders and carry spreading cams, one of which In additionl it provides a@ is shownV at |`H, Figure 14, for spreading the brake shoes. The cam shafts |09 and H0 have levers H2 and H3 secured thereto. These levers are operated by a cross head H4 and a brake rod H5 that lead to an air diaphragm I0. The connections from the levers H2 and H3 to the cross head H4 is by means of links H1 and H8. A bracket H9 on the wheel arm supports the brake rod H5 and its air diaphragm l I6.

Referring now to Figures l0, ll, l2- and 13, these gures illustrate my invention as applied to the support of a vehicle body |0 by dual wheels H and |2'. 'Ihe brackets I5 and I6' mount a trailing wheel arm |'i in the same fashion as in the main form of the invention. For the sake of clarity none of the brake mechanism is shown in connection with the modification. A load strut I9' is connected to the wheel arm Il', a bracket 12' and a yoke 15 in the same manner as in the main form of the invention. The wheel axle I8' and the wheels are mounted in the same fashion as in the main form of the invention. In connecting the load strut I0 to the torsional spring unit 22 the construction is however, slightly different from that shown in the main form of the invention. Brackets |20 and |2| are secured to the vehicle body I0 and serve to mount the torsional spring assembly 22' in the manner illustrated in Figure 12. These brackets are desirably made of two sections bolted together with provision, as indicated in Figure 13, for a limited amount of adjustment of the lower section with respect to the upper section. The central member 29 of the torsional spring has lever arms |22 and |23 at its ends. These lever arms are secured in tapered bearings |24 and |25 on the brackets |2| and |20 by pin portions |26 and |21 on the lever arms |22 and |23 and rubber bushings |28 and |29. The bushings |28 and |29 are held under compression by cap washers |30, bolts |3| and nuts |32. The connection of the load strut |9 to the outer member 34' of the torsilastic spring unit 22' is identical with that in the main form of the invention.

In this modied form of the invention, the spring 22 is free to move about the mountings in the brackets |20 and |2| when load is applied thereto through the load strut I9. This is illustrated by comparing Figures l1 and 13. In Figure 11, for example, the arms |22 and |23 are iny direct alignment with the lever arms 6|' and 62'. In Figure 13, the load has moved the load strut I9 upward, this has caused a corresponding upward shift of th-e spring and the lever arms 6| and 62. At the same time the load has caused a'rotation of the shell portion 34' and the spring 22. Further upward movement of the load strut I9 increases the turning movement of the outer shell 34 with respect to the tube 29 and at the same time shortens the effective leverage of the lever arms 6|' and 62', |22 and |23.

It should be noted that through the construction described herein all of the pivotal connections are made by means of tapered rubber bushings so as to eliminate the necessity for oiling and to avoid bearings that wear and become loose. These tapered rubber bushings in addition, provide a certain amount of cushion against road shocks and thus greatly lengthen the life of the device. All of the weight of the vehicle is spring mounted, the only parts not so mounted being the wheels, the trailing arms and the load struts. This is in itself of great importance in eliminating wear and tear due to minor road shocks that are always present. The manner of mounting the wheel arms and load struts provides a con-V siderable degree of ilexibility for the wheel units. Ine wheel of a pair may ride over a bump with little strain on the mechanism because the rubber bushings permit the necessary yield. In the tandem construction, if the front wheels are elevated or dropped suddenly, the torsional spring mounting and the connecting link 33 reduce the shock by automatically causing the rear wheel to be placed under a greater spring pressure from the torsional spring. The individual wheel mounting is of great advantage in eliminating tire wear on curves. The outer wheels merely roll faster than the inner wheels and there is no dragging or skidding as a result.

It is believed that the nature and advantages of my invention will be clear from the foregoing description. Having thus described my invention, I claim:

1. In combination with a vehicle body a wheel arm pivoted on the body and extending downwardly at an acute angle to the body, a wheel supporting the lower end of the' arm, a load strut also supported by said wheel and extending upwardly and away from the wheel arm toward the body, a lever arm pivoted on the other end of the load strut and extending angularly downward and away from the load strut, a second lever arm pivoted on the body, and means, including a spring under tension, connecting the free ends of said lever arms.

2. In combination with a vehicle body a pair of wheels spaced apart in tandem, a trailing wheel arm supported on each wheel having its upper end pivotally mounted to the body, a load strut supported by each wheel and pivotally connected to the corresponding wheel arm, a torsional spring mounted on the body adjacent the upper end of each load strut, means connecting one end of each spring to the upper end of its adjacent load strut, and a link under compression between the other ends of the two torsional springs to balance the loading of the springs.

3. In combination with a vehicle body a pair of wheels spaced apart in tandem, a trailing wheel arm supported on each wheel having its upper end pivotally mounted to the body, a, load strut supported by each wheel and pivotally conn ected to the corresponding wheel arm, a torsional spring mounted on the body adjacent the upper end of each load strut, means connecting one end of each spring to the upper end of its adjacent load strut, and an extensible link under compression between the other ends of the two torsional springs to balance the loading of the springs.

4. In a wheel suspension for a vehicle body, a trailing wheel arm having means at its lower trailing end to mount a wheel, said arm having lateral extensions at its upper end for mounting the arm to the body, spaced bearing brackets on the body adapted to support said lateral extensions, said wheel mounting means comprislng an axle, two wheels rotatably mounted on said axle with the trailing arm between them, a load strut extending upwardly from the wheel mounting end of the trailing arm, and a torsional spring connecting the upper end of the load strut to the body.

5. In a wheel suspension for `a vehicle body, a trailing wheel arm having means at its lower trailing end to mount a wheel, said arm having lateral extensions at its upper end for mounting the arm to the body, spaced bearing brackets on the body adapted to support said lateral extensions, said wheel mounting means comprising an axle, two wheels rotatably mounted on said axle with the trailing -arm between them, braking mechanism for said wheels mounted on the trailing wheel arm, a load strut extending upwardly from the wheel mounting end of the trailing arm, and a torisonal spring connecting the upper end of the load strut to the body.

6. In a wheel suspension for a vehicle body, the combination of a trailing wheel arm and a load strut pivoted together at their lower ends and diverging upwardly toward the vehicle body and connected thereto, means supporting the lower ends of the wheel arm and load strut comprising two separately rotatable Wheels and axle means therefor, the load strut being connected to the body by a lever arm pivoted to the upper end of the strut and extending downwardly and rearwardly away :from the strut and a torsional spring connected to the lever arm and to the body and urging the lever arm in a direction to push the load strut forwardly endwise toward the trailing arm.

KEITH W. TANTLINGER.

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